CZ2013858A3 - Bismuth-based energetic materials - Google Patents

Abstract

A bismuth salt-based energy compound having initial explosive properties obtained by reacting soluble bismuth salts with soluble salts of inorganic and organic energy compounds, wherein the soluble bismuth salt is based on bismuth perchlorate. The following describes a method for its preparation and use.

Description

Bismuth-based energy materials

Field of technology

The invention relates to bismuth-based energy compounds, to a process for their preparation and to their use.

State of the art

In recent years, there has been increasing pressure on manufacturers engaged in the production and processing of so-called "energy materials", meaning explosives and pyrotechnic mixtures, including ammunition manufacturers to completely remove all toxic materials, especially toxic metal compounds - see _below . It is the cations of these, mostly noble metals, bound in organic and inorganic molecules that are completely irreplaceable, because they form compounds that have served for over 100 years as excellent primary explosives - explosives, which are the main component of ignition systems for ammunition of all calibers and different types of detonators.

Ammunition manufacturers are focusing on replacing the lead salts of polynitrophenols, such as lead trinitroresorcinate, which is the basic explosive, and possibly other compounds, such as lead dinitro o-cresolate, in electric igniters. In the past, lead and diatomaceous earth lead lead are now used as an auxiliary explosive. Since the beginning of the last century, these compounds have gradually replaced the now legendary mercury fulminate, which is an extremely toxic but also an irreplaceable compound characterized by extremely high T flames and thus extremely high ignition ability.

The irreplaceability of salts of heavy, more noble metals, such as lead, with aromatic polymer compounds or with other energetic compounds having acid properties, such as nitrogenous heterocyclic compounds - tetrazoles, etc., lies in the release of enormous heat generated by condensation of these relatively low-boiling metals. . This heat is then transferred to the dust charge, for example, and thus the maximum efficiency of heat transfer and the achievement of the required ignition Ίζ These explosives is achieved. mixed with other components, such as a suitable pyrotechnic system, which mainly ensures the prolongation of the ignition pulse and the creation of a sufficient amount of condensed products with the highest possible heat capacity, will make the heat transfer even more efficient. However, the above-mentioned explosives are not capable of independent function in the match - they do not have sufficient sensitivity

This is a combination of friction and impact, with friction significantly predominating here and some of which show too high a brisance. Then it is necessary to use other so-called auxiliary components of so-called sensitizers or frictionators, which can be basically 2 types of materials: active and inert. Other explosives having a substantially lower flash point than the base explosive can be used as active sensitizers. Friction of the crystals of the parent explosive during injection with an anvil or injection needle releases a certain amount of heat which, depending on the intensity of heat dissipation, causes a local increase fpXd, which is lower than the point of explosion of the base explosion, does not initiate. In the presence of a few percent of active sensitizers with a lower flash point, this is initiated and the released heat of reaction ignites the main explosive. This is how the proven TNRO - Tetrazen system has been working for 100 years. Due to the fact that tetrazene, like many other metal-free explosives, is soft, its amount must not exceed a certain limit value - on the order of several percent, otherwise it will not release enough heat by friction. If tetrazene-like compounds were used as the main explosives, the second principle mentioned above comes into play - the use of an inert material whose grains will be evenly dispersed in the explosive and will act as accumulators of thermal energy, which concentrates on their surface and again causes local increase In principle, therefore, it must be a high-melting compound with bt significantly exceeding the explosion points of known explosives - ie. min 550 ° C and mainly thermally and thermally non-conductive. These properties are extremely important because non-stationary processes take place here and it is necessary to compensate for the heat dissipation of the surroundings. Here, however, not only the amount but also the size of the particles is important - it depends on whether the material will function as a real sensitizer or if it will only be a useless ballast, which also undesirably cools the mixture. Many years of experience and research to find optimal frictionators have shown that ground glass is the optimal material - generally "glassy" materials and some high-melting sulphides, such as antimony sulphide, used for almost 200 years, both in mixtures with mercury fulminate , as well as in mixtures based on TNRO, where they perform the function of both fuel and frictionators. From an ecological point of view, however, it is unsatisfactory. The use of ground glass is also problematic - there is a difference between the material generated by the fragmentation of glass waste from glass companies used by many munitions companies and the material ground by, for example, ball mills, which has a more uniform structure but also lower sensitization ability. and the edges on which energy is concentrated. However, when using "fragmented" waste, a technological problem arises - to obtain a sufficient amount of the required fraction from the total amount of waste material. This type of glass, however

2 'can additionally cause undesired single activations, for example in drop tests of lower limit matches.

From the above it follows what should be the optimal properties of the main, carrier explosive, usable in matches of ammunition in terms of optimal function: maximum sensitivity to puncture, preferably without the use of frictionators, minimum brisance, high content of condensed products in fumes and high mechanism efficiency. heat transfer from products to propellant. Today, however, there are other aspects: 1. stability - requiring high thermal stability due to thermal decomposition temperature and chemical stability - the material must not react with air humidity, atmospheric gases and other materials used in ammunition production and must not be subject to changes in daylight - ie. must not contain Ag compounds. 2. ecological - the material must not contain toxic metals such as - Pb, Hg, Sb, Ba, nor must it contain perchlorates, which were also found to be toxic.

The basis must be an organic or inorganic compound containing certain functional groups in the molecule, which in accordance with today's modern concept of explosiveness are defined as so-called explosives - "explosive carriers". It is usually a combination of two or more electronegative elements, whose bonds are less strong, ie. they have low binding energy and these groups then introduce a certain degree of instability into the whole molecule, which we call explosives. Such compounds then have the ability of exothermic decomposition, which releases Gibbs free energy and produces more stable products, i. having stronger ties. This basic principle, derived from the principles of thermodynamics and reaction kinetics, applies to both compounds and explosive mixtures.

The above-mentioned functional groups, such as nitro group - NO ₂ , nitroso group - NO, hydrazino group - NHNH ₂ , hydroxylamino group - NHOH, nitramino group - NHNO ₂ , hydrazo group - HN-NH-, azo group -N = N-, azido group - N ₃ "diazo" - N ₂₊ , furoxane "and" are generally known and in combination with both aliphatic and cyclic aromatic and heterocyclic compounds; they form hundreds of explosive compounds, now collectively called "energetic materials." Most of these compounds were discovered and described about 100 years ago, but those with acid properties and therefore the ability to form salts, with both inorganic and organic bases, and especially with some noble, but mostly toxic, metals, have found the greatest application. . Today, the historical mercury fulminate and then mainly the lead salts of aromatic polynitrophenols, which appeared in the early 20's and azides, are the most successful explosives that have ever been used, especially in matches.

Since the beginning of the last century, there have, of course, been efforts to replace these toxic compounds with less toxic compounds, i.e. without toxic metals - mainly mercury and lead, or barium. E.g. tetrazene, discovered in 1910, is a purely organic compound, but its properties predetermine it only as an active sensitizer of other explosives - such as lead trinitroresorcinate. It itself has too complicated a molecule, so the explosive decomposition is relatively complex and long, and thus the explosive T is very low, similar to other explosives containing guanyl in the molecule. Add to this the thermal instability and extreme susceptibility to over-pressing, this explosive can never fully replace TNRO and cannot meet the above requirements. Similarly, dinitrodiazophenol - Dinol, DNDP, which was discovered as early as 1858 and used exclusively in the dyeing industry, before its explosive properties were discovered after another 100 years or so, and was first used to detonate in the United States. ecological "explosive in the famous German match composition Sintox. The main problem in terms of function is excessive brisance and low content of condensed products in the exhaust. From the point of view of ecology, then, unpleasant physiological properties, manifested during handling - irritate the skin and mucous membranes. Due to the strongly negative oxygen balance, its matches do not undergo perfect explosive decomposition and toxic fragments of the aromatic polynitrosystem are released. In terms of stability, in the case of dinol, instability is also pointed out, which is manifested by intense color changes by daylight, which is typical for all diazo compounds. Another explosive, also discovered at the beginning of the last century - dinitrobenzofuroxane, has no problems with chemical or thermal instability, but its very complicated production, based on highly toxic compounds such as trinitrochlorobenzene, puts a heavy strain on the environment, not to mention extreme sensitivity to static electricity.

Heterocyclic nitrogen compounds were also discovered at the end of the 19th century, the best known of which are five-membered heterocycles with one carbon and two substitutable hydrogens - tetrazoles. Their chemical, physical and explosive properties vary widely, mainly according to the functional group (see above), which substitutes for carbon-bound hydrogen - ie. in position 5. This creates a very diverse group of compounds from non-explosive, having a wide range of applications in the chemical and pharmaceutical industries (alkyl and aryl, thio and cyano derivatives) through energy compounds (amino, hydrazino derivatives or bistetrazole, which is a combination of two tetrazole cycles). typical explosives (halogen, nitroderivatives, nitraminoderivatives, diazoaminotetrazole and azotetrazole, which is a combination of two tetrazole cycles by azo group) to extremely explosive azidotetrazole and diazotetrazole, considered one of the most unstable and dangerous very known compounds, because it has the ability to solutions! It is because of these few compounds that this large group of substances has been mistaken for dangerous explosives, and 90% of them have found use in many other fields. Since tetrazoles are acidic in nature and, depending on the substituent, they are therefore weaker or stronger acids, they are able to form salts of inorganic and organic bases as well as metal salts. It is these salts, especially the salts of noble and heavier metals, that have aroused the interest of explosives for about 100 years. Lead, barium, silver, mercury and copper salts are the subject of dozens of patents, mainly from the 1920s to the 1950s. Despite this particular interest, few cases of practical use of these salts have been reported. In the last century, the basic lead salt of 5,5-azotetrazole was introduced in Germany, and around the 1980s, the mercury salt of 5-nitrotetrazole was introduced into the United States, exclusively in detonators, as a much more chemically stable but not an ecological substitute for lead azide.

The applicability of salts of inorganic and organic bases depends on their stability, which is directly relevant to the stability of the base. Salts of weak bases such as ammonia, hydrazine or hydroxylamine are less stable, while salts with guanidine and its derivatives (amino, diamino and triamino guamdines) are highly stable and are at their peak today. Over the last 20 years, dozens of patents have been filed for the use of these compounds in propulsion systems - rockets, gas generators and modern, non-azide airbag infills. However, these compounds do not have explosive properties.

There are also condensation products of some tetrazoles with aromatic polynitro compounds, which were first patented in Germany in 1957. They are prepared by reacting alkaline salts of tetrazoles with chlorine derivatives of organic polynitro compounds or with tetranitroaniline. For example, 5-nitrotetrazole sodium or 5,5'-bistetrazole disodium salt is reacted with picryl chloride or styphyl dichloride to form picryl-nitrotetrazole or styhyl-bis-nitrotetrazole or dipicryl-bis-tetrazoles. Similar compounds are produced today by the German company Dynitec. They have explosive properties but are only used for special purposes.

Another group of compounds are those in which tetrazoles have the function of weaker or stronger bases and can therefore form salts with other explosive compounds having the properties of acids - polynitrophenols, hydrochloric acid, perchloric acid and dinitramide. German scientists are researching these compounds. It is possible to start, for example, from 5-aminotetrazole, the acidity of which is reduced by methylation to 2-methyl or to a 2,4-dimethyl derivative. The first is a weak base, able to form salts only with strong acids, the second is a stronger base, able to form salts with weaker acids to form the corresponding azides and dinitramides. As expected, only perchlorates have the properties of explosives, but they are now considered to be

X toxic, not to mention the corrosive products of thermal decomposition and dinitramide salts, which was discovered in the 1970s in Russia, but to date its sufficiently cheap industrial production has not been solved. Other tetrazole derivatives have also been discovered - such as bis-tetrazolyl amine BTA, which is an energy compound but not an explosive.

There is still a group of complex and double explosive salts. Such historical compounds, discovered by Swedish chemist E. Stabba in the 1960s and called stabanates, are the double metal salts of 5-nitraminotetrazole and 5,5 'diazoaminotetrazole with styphnic acid. Unfortunately, these are only lead salts. Other compounds where tetrazoles form complex salts with some anions of inorganic acids (perchloric, nitric, azic anhydrous) and some metal cations are also historical compounds, designated CP (pentaamine 5-cyano-2H-tetrazolato-N2 cobalt (III) * perchlorate or similar BNCP (tetraamine-cis-bis-5-nitro-2H-tetrazolato-N2-cobalt (III) perchlorate.

Modern patents, e.g. DE 102010036950 A1 in recent years, disclose similar complex compounds, but without the undesired perchlorates, where the central atom is formed by one of the transition elements, preferably Co, which forms complex cations such as positively divalent pentaamino cobalt azide, or positively monovalent tetraamino cobalt diazide, or similar ions pentaamino cobalt nitrate or tetraamino cobalt dinitrate, which form salts with anions of explosive tetrazole derivatives such as 5-nitrotetrazole, 5-nitraminotetrazole, 5,5-azotetrazole and optionally 5,5'-diazoaminotetrazole. Examples of the resulting products are - pentaamine (azido) cobalt (III) azotetrazolate, Pentaamine (azido) cobalt (III) nitrotetrazolate and pentaamine (azido) cobalt (III) nitraminotetrazolate. However, these compounds contain cobalt, which, like nickel, is now classified as a toxic element by modern criteria. These compounds have a very low sensitivity to friction, so in this respect they are more like explosives and their use in matches would be associated with great difficulty - the need for extreme sensitization. The authors also disclose simple metal salts of basic explosive tetrazoles (5-nitrotetrazole, 5-nitraminotetrazole, 5,5'-diazoaminotetrazole and 5,5'-azotetrazole) as Fe, Cu and Na salts. The Fe and Na salts are again characterized by a very low sensitivity to friction, not to mention the variable content of crystal waters (mainly Na salts) and, conversely, the Cu salts (mainly 5-nitrotetrazole and 5,5'-azotetrazole) are handling and high explosives. Even these compounds cannot be recommended for matches. The authors also mention mixtures based on, for example, copper styrate, which is a tetrahydrate and become explosive only after dewatering, and even mixtures based on styric acid itself, which is of course not an explosive. Ingredients, based on $

according to the authors, they must contain an extremely high amount of sensitizer on these compounds - up to 47% of ground glass!

Similarly, another patent, WO 2007/071650, proposes a double potassium-calcium salt of styphnic acid as a "new" explosive. Similar compounds are known and are described in the monograph Bubnov, Suchov - Initiating the Encouragement. This "new" salt has an extremely high flash point of 350 <400 ° C and the authors propose this compound mainly for non-azide and thermostable airbag compositions. Its use in matches would be due to the already mentioned extremely high b.v. and low friction sensitivities are also extremely problematic.

Complex compounds, where the function of the central atom is performed by a divalent iron or copper atom, the function of the ligand is performed by the 5-nitrotetrazolate anion in an amount of 3 to 6 ions. In case less than 6 mttetrazolate anions are bound to the central anion, the remaining ones are replaced by water molecules. These bulky complex compounds form salts with inorganic (Na ⁺ , Ca ²⁺ , Mg ²⁺ and NH 4 ⁺ ) or organic cations (hydrazonium, nitrosocyanaminium, 3,3-dinitroazetidinium, 5-amino-1-nitroso-1,2, 3,4-tetrazolium, 1,5-diamino-4-nitroso-1,2,3,4-tetrazolium, 1,2,5-triamino-1,2,3-triazolium, 3,6-bis-guanidinium 1,2,4,5-tetrazine, 3,6-bis-nitroguanidinium-tetrazine and 3,6-bis-hydrazinium-tetrazine and others). Examples are diammonium diaquatetrakis- (5-nitrotetrazolato-N2) cuprate or ferrate. These compounds, like all other complex compounds, have a complex and very bulky molecule with a high content of organically bound nitrogen, which together with a balanced oxygen balance will undoubtedly ensure high performance, especially in terms of a large number of gaseous products. In terms of reaction kinetics, very complicated thermal decomposition can be expected for such large and complex molecules, which is usually manifested by a reduction in the flame temperature. In addition, these compounds do not have the heat transfer mechanism described above, which is used in the phase changes of low-boiling metal vapors. Their commercial use in ammunition matches is not yet known and the authors recommend these compounds exclusively for detonators. The compounds were patented by the Los Alalmos National Laboratory (LANL) in 2006 under US2007 / 011751.

From the above-mentioned introductory balance, it follows that in the last 50 years, there have been no significant discoveries in the field of explosives, especially explosives in the composition of ammunition. Today, this is reflected in the lack of suitable compounds that would be able to fulfill the role of so-called green explosives, meeting the demanding conditions for environmental protection.

The essence of the invention

The present invention relates to the production and use of novel energy compounds with reduced toxicity based on bismuth salts which will be able to best replace explosives, such as lead tricinate, which have optimal properties for this purpose and are considered by those skilled in the art to be essentially irreplaceable. As mentioned above, this "irreplaceability" is mainly due to the presence of a heavy, more noble metal, which is bound by weak and easily fissile bonds and also provides a highly efficient heat transfer mechanism.

Unfortunately, the Periodic Table of Elements offers a very limited selection, but there is a metal that, although one of the heaviest elements known, its toxicity is considered by modern criteria to be one of the lowest compared to many other metals used in munitions production. This is bismuth (Bi), belonging to group 5.A of the Periodic Table, which is in the same subgroup with the incomparably more toxic arsenic and antimony. In terms of some physical properties - such as b.t. and b.v. and density is similar to lead, in terms of molten behavior when it has a higher density than solid, it is more like arsenic, antimony and / or solid water, which predisposes it for use in special alloys that perfectly fill the form, such as lithium, further into special low-melting eutectic alloys with use in thermal fuses and special solders. In the last few decades, Bi has also penetrated ammunition production, where in special alloys it serves as a replacement for lead shot and projectile cores. Its oxides and oxinitrates, of variable composition, are increasingly used in modern, non-toxic pyrotechnic compositions as oxidizers, and some non-explosive Bi salts are used in modern propellants as ballistic modifiers. Other technical applications include - thermocouple material, U - 235 and 233 nuclear reactor carriers, Bi telluride semiconductors, BiSrCaCu mixed oxides as superconductive materials. Especially in the 1990s, research intensified to maximize the use of Bi as a non-toxic lead substitute. Bi in the form of vanadate has been designed for non-toxic pigments, lubricants, as a catalyst in the production of acrylic fibers, etc. It is also widely used in medicine, both in historical and in modern pharmaceutical and cosmetic preparations. For these purposes, only the so-called oxidosols (basic salts or subsoles) Bi are used. They are water-insoluble compounds having internal and external uses (subnitrate, subcarbonate, subcitrate, subgallate and subsalylate) and are used as antidiarrhea, for the treatment of gastrointestinal diseases, for the treatment of internal and external infections, peptic ulcer and skin diseases.

This is how Bi differs from other heavy metals - due to its extreme susceptibility to hydrolysis, both in aqueous solutions and in solutions of some polar solvents. The hydrolysis takes place quantitatively with the exclusion of basic products, called oxidosols (subsoles, or basic salts). The solubility of these salts is so low that many of them are used for the gravimetric determination of Bi. Bi forms some of the least soluble known compounds at all, eg Bi ₂ S ₃ - pS (negative logarithm of solubility product) = 97!

Hydrolysis in aqueous solutions proceeds according to the scheme:

In general: BiX ₃ + H ₂ O = BiOX + 2 HX where - X = inorganic acid anion (eg NO ₃ -, Cl -, ClO ₄ - or an organic acid residue).

One mole of the "normal" bismuth salt produces 1 mole of oxidosole (basic salt) and 2 moles of the corresponding acid. In most cases, the released acid is not sufficient to acidify the solution sufficiently to keep the Bi ions in a dissolved state and Bi to precipitate as its basic salt (oxidosole), making it of course unusable for further precipitation (e.g. some explosive salts). A solution of sufficient concentration suitable for practical use would have to be strongly acidified, but in such acidic solutions many compounds no longer precipitate or decompose. In addition, diluting such solutions with a precipitant solution that additionally reduces the acid anion concentration by binding it to the metal cation forming the corresponding salt of the precipitated compound again increases the likelihood of precipitation of undesired hydrolysis products. This may be the main reason why no explosive salt has been prepared so far. to the product of solubility.

In addition, as the following table shows, Bi forms a number of aqua-oxo-hydroxo complexes in aqueous solutions depending on the pH. Since the water molecule is uncharged, we can easily deduce the composition of the anhydrous complex, the existence of which can then be assumed in the anhydrous precipitate - provided, however, that the above-mentioned undesirable phenomena do not occur.

1 / Positively trivalent hexaaquocomplex Bi (H ₂ O) ₆ or anhydrous Bi (3+) - normal salt.

2 / Positively divalent pentaacohydroxo complex Bi (H ₂ O) ₅ OH or anhydrous Bi (OH) (2+)

3 / Positively monovalent tetraahydrohydroxo complex Bi (H ₂ O) ₄ (OH) ₂ or bez Bi (OH) ₂ (+)

4 / Positively tetravalent tetraacohydroxo complex (BiO) ₅ (H ₂ O) ₄ OH or bezv (BiO) ₅ OH (4+)

5 / Octahedral positive hexavalent diacocomplex (BiO) ₆ (H ₂ O) ₂ or Bi ₆ O ₄ (OH) ₄ (6+)

6 / Positive hexavalent hexaoxo complex (BiO) ₆ (6+) or simply BiO +

It follows from the above that the preparation of Bi salts by the double exchange method is not a simple matter.

One possibility is to use very dilute solutions, which are used in analytical chemistry - 0.1 <0.01%, where acidification to a level of about 0.1 M is enough to keep the Bi cations in solution and it is then possible to precipitate them with the compound whose Bi salt has a sufficiently low solubility product (high pS). Thus, Bi can be determined gravimetrically, for example, as oxoformate, oxinate or pyrogallol salt. However, the use of such dilute solutions is very inefficient for production.

In analytical chemistry, the addition of complexing agents, such as tartaric acid, which binds Bi ions to the soluble complex, is also used, especially in cases where precipitation is performed in a slightly acidic environment. However, experience has shown that the displacement of bismuth ions from these complexes is very difficult.

Of course, Bi compounds can also be prepared by simply dissolving metallic Bi, its oxide (Bi ₂ Os) or oxocarbonate (BiO) ₂ CO 2 in the corresponding acid - but this applies mainly to salts of strong, inorganic or organic acids.

All the above methods have been practically tested in the research of explosive salts Bi - mainly salts of aromatic polynitro compounds, azides and some selected tetrazoles. By simply dissolving the oxide and oxocarbonate Bi in saturated solutions of aromatic polynitro compounds, the salts could not be prepared, even under boiling, because the reaction '»3 · S ♦ J1 *' ¹ 5 9 and 9 ^{J s} . ' ¹ · »j' * ··· ..,> * J4 '' ^ν ·« »· ·», ₄ did not occur at all. The double exchange method, which was then used as the only alternative, using commercially available Bi salts, such as chloride or nitrate, produced various, mostly non-explosive products. In exceptional cases, it was possible to prepare products with indistinct explosive properties, and only in the field of tetrazoles

Finding a suitable Bi salt useful as a universal precipitant, optimizing precipitation methods for particular compounds, and describing these compounds in terms of explosive properties are the main objects of the present invention.

A suitable precipitant which is capable of providing sufficient Bi ions in sufficiently concentrated solutions without the need to increase their acidity or the use of complexing agents is bismuth oxochlorate according to the invention.

It is generally known that very bulky anions - chlorates (C1O ₃ -) and especially perchlorates (C1O ₄ -) have a strongly dislocated charge, and thus a very low affinity for cations. This property is practically manifested by extreme solubility not only in water, but also in a number of polar and non-polar solvents - it mainly applies to perchlorates. Perchlorates form the most soluble salts, with the exception of potassium, cesium and rubidium salts, but this extreme solubility is not due to association with solvent molecules. Perchlorates of precious, heavy metals are no exception. To clarify, we present the values of Gibbs free energy needed to form the free anion in solution (vkJ / mol): nitrates - 109, chlorides - 131, perchlorates - 8.5.

In accordance with this theory, Inorganic Chemistry (H. Remy 1961) describes the compound perchlorate Bi, which is precipitated from concentrated perchloric acid as a normal salt Bi (C10 ₄ ) ₃ x 5H ₂ O, which is hydrolyzed to oxochloroacetate - BiOClO ₄ by dilution. x H ₂ O, crystallizing in the vaults as a monohydrate and further diluted to hydrate to acicular trihydrate. All these compounds are perfectly soluble in water - even without the addition of acid and form a clear and perfectly stable solution.

Since Bi perchlorates are not commonly commercially available, a method for their preparation and possible isolation has been developed. The method is based on the simple dissolution of Bi oxide or oxocarbonate in commercially available, about 70% HClO ₄ . The product can then be isolated by filtration or, after dissolving in water, made up into a volumetric flask to a solution of known concentration or the precipitated oxochlorate precipitated from aqueous solution with organic solvents (see working examples).

A number of explosive compounds were prepared by simple precipitation in aqueous solutions, namely: Bi salt of hydrogen azide, Bi salts of the basic series of aromatic polynitrophenols picric acid (TNF), styric acid (TNR) and trinitrofluroglucin (TNFG), and 4,6 dinitroazidophenol (DNAF) and 4,6-dinitrobenzofuroxane (DNBF) and Bi salts of selected explosive 1-H-5-substituted tetrazole derivatives.

Due to the fact that in most cases very insoluble amorphous to colloidal precipitates formed, boiling precipitation methods were used if possible to improve the filterability and the order of addition of the solutions was chosen so that precipitation took place from the beginning in the most acidic possible environment and achieved the most crystalline products. The precipitation can, of course, be carried out under a variety of conditions in terms of adjusting the concentration and pH of the solutions, the reaction temperature and the method of pouring the precipitated solutions. This can affect how Bi will be bound in the molecule via one of the above-mentioned cations. This can, to a certain extent, affect the explosiveness of the resulting compound, which depends not only on the total metal content in the molecule, but also on the nature of the bonds in terms of the energies needed to break them down - activation energies.

Therefore, the Bi content in the prepared compounds was determined analytically, and on the basis of the obtained results, it was derived which of the above-mentioned Bi cations is bound in the compound and in what number.

The compounds were further subjected to differential thermal analysis (DTA) thermal tests and conventional explosive tests - flame sensitivity and friction sensitivity.

Examples of embodiments of the invention

The following table shows examples of energetic compounds prepared by the method of the present invention.

starting compound proposed formula of the prepared compound Bi content (% by weight) B.V. (° C) friction sensitivity Sodium azide BiON ₃ 78 320 Sodium picrate (NO ₂ ) ₃ C ₆ H ₂ OBiO 46 240 - Sodium styphnate (NO2) ₃ C ₆ H (OBIO) ₂ 60 220 - Sodium trinitroflucinate (NO ₂ ) ₃ C ₆ (OBÍO) ₃ 67 175 -

4,6 - sodium dinitroazidophenolate (NO ₂ ) 2C _b H ₂ N3 (OBiO) .Bí2O3 75 200 - 4,6 - dinitrobenzofuroxanate dras. (NO ₂ ) 2C6H2N ₂ O2BiO 46 220 - Sodium 5,5 '- azotetrazolate N ₁₀ C ₂ B 12 (OH) ₄ 64 180 + Sodium 5,5 '- azotetrazolate N | oC ₂ (BiO) ₂ 68 180 + Sodium 5,5'-azotetrazolate N ₂ O ₄ (BiO) ₅ OH 71 180 + Potassium 5-nitramaminetetrazolate N ₅ CHNO ₂ Bi (OH) 2 56 190 - Sodium 5,5'-bistetrazolate N ₈ C ₂ Bi ₂ (OH) ₄ 67 280 + Sodium 5,5'-diazoaminotetrazolate Ni | C ₂ BÍ3 (OH) ₆ 69 240 + Sodium 5,5'-bis tetrazolylhydrazinate. N ₂ O ₄ H ₄ (BiO) ₅ OH 70 150 + Sodium 5 - nitrotetrazolate N ₄ CNO ₂ Bi (OH) ₂ 58 196

The optimal precipitation method had to be chosen for each compound in order to obtain the best filterable products - this is especially true in cases where the solubility of the resulting precipitate is so low that it precipitates in the colloidal state (5.5'-azoetrazole salts, 5.5 - diazoaminotetrazole, 5,5'-bis-tetrazolylhydrazine and TNFG salts), on the other hand, azides and picrates are substantially more soluble and precipitate in a well filterable amorphous or microcrystalline form. Therefore, proven principles have been tested - precipitation at boiling and in the greatest possible dilution, which will increase the solubility of the precipitate and eliminate it in a more filterable form. In practice, however, it has been shown that the best results can be obtained in the most concentrated solutions, because we precipitate with acidic solution of oxochloroacetate Bi, which contains hydrolysis released HClO ₄ and concentrating these solutions significantly lowers the pH, which has been shown to form crystalline compounds Bi strongest influence ever. For some compounds that decompose in a strongly acidic environment (5,5-azotetrazole, azide, 5,5-diazoaminotetrazole), boiling precipitation had to be omitted because of large compound losses. However, in the cold, the Bi salts of these compounds are remarkably stable even in a strongly acidic environment, even though their sodium salts, for example, decompose immediately under the same conditions.

Therefore, a number of volumetric Bi oxochlorate solutions with known Bi ion concentrations have been prepared - for example 0.02 g / ml, 0.2 g / ml and 0.45 g / ml, which is the strongest solution that can be technically prepared. Stronger solutions can no longer be transferred to a flask.

Of course, the so-called normal perchlorate Bi pentahydrate was also isolated from concentrated perchloric acid - but this extremely moist and unstable compound is not suitable for practical use.

Oxochlorostat Bi was also isolated from the concentrated wash solution by precipitation with alcohol. If methanol or ethanol was used, precipitation took place over several days; if isopropanol was used, the product precipitated immediately. This compound was then used to precipitate Bi salts of selected compounds whose explosive properties were found to be most pronounced or in cases where precipitation failed in strongly acidic solutions.

The differential thermal analysis (DTA) assay tested 20 mg of sample and was heated at the usual rate of 5 ° C / min. In the absence of an explosion or detonation, but only an exothermic reaction (for Bi salts of 5-nitraminotetrazole, 5,5'-bis tetrazole, 4,6-dinitrobenzofuroxane and 4,6-dinitroazidophenol), the heating rate was increased to 20 ° C / min. Then there was always detonation, with the exception of Bi salt 4,6-dinitrobenzofuroxane, where only deflagration and Bi salt 4,6-dinitroazidophenol, where only exothermic reaction occurred.

Friction sensitivity was tested by rubbing with a pestle in a porcelain dish. If not initiated, the compound is considered insensitive to friction compared to conventional explosives. However, for most compounds that did not initiate, a black trace formed directly below the pestle, which means that there is a reaction here, but the reaction is not transferred to the other material. The compounds that showed friction sensitivity (Bi salts of 5,5 'azotetrazole and 5,5'-diazoaminiotetrazole and 5,5'-bis-tetrazole and 5,5'-bis-tetrazolylhydrazine) were subsequently determined to be friction sensitive to friction sensitivity (PCT) instruments.

PCT sensitivity compared to TNRO.

Compound load g / at 0% activations load / g / at 100% activation 5.5 '- azotetrazolate Bi 500 2800 5,5 '- diazoaminotetrazolate Bi 700 2000 5,5 '- bis-tetrazolate Bi 5000 8000 5,5 '- bis-tetrazolylhydrazinate Bi 6000 12000 TNRO 150 500

As the table shows, the friction sensitivity is lower compared to TNRO and in this respect these explosives can be considered safer to handle. However, due to the high sensitivity to injection, especially in the first two, they show an excellent function in all types of matches with central ignition and in cartridges with edge ignition.

Due to the significantly higher metal content compared to TNRO, weaker explosive properties can be expected - longer match reaction time, which was confirmed by Drop-Test tests, which compared the pressure and time pulse of pure 5.5 '- azotetrazolate Bi with common types of Neroxin compositions , containing 30 ^ 40% TNRO - the results were comparable, only for pure explosives more uniform and reproducible values were achieved. Unfortunately, a comparison of both explosives in the pure state is not possible with this method, because TNRO is not possible to cause an explosion under the given conditions.

All of the compounds listed below are flame sensitive and deflagrate or detonate upon ignition. Only Bi salt - 5,5'-bis tetrazole, showing according to DTA the highest B.V. it is significantly less sensitive to the flame and when ignited by the flame, it overheats and thus detonates.

The friction sensitivity test was performed by rubbing a porcelain pestle loaded with a variable load on a porcelain plate containing several mg of the test compound. The test is highly subjective and its results only make sense in comparison with other, already established compounds, whose sensitivity to friction is known and is still being tested for many years. Due to the fact that tetrazene, which begins to activate at a load of 900 Λ,000 g, is considered to be the least friction-sensitive industrial explosive, the sensitivity of the above-mentioned compounds was evaluated with respect to tetrazene. If the compound has a significantly lower sensitivity, it is marked with a - sign, in the case of a sensitivity of the order of magnitude, with a + sign. - these compounds could be potential adepts for use as main (carrier) explosives in matches and detonators. The others, as explosives additional or usable in case of different methods of activation - resistive bridge, spark, or laser beam.

The proposed formulas were derived from the bismuth content, determined by complexometric titration to xylenol orange at pH 2-3. The proposed formula of the compound formed from 4,6-dinitroazidophenol is not given in the table, because the Bi content, determined by titration, is substantially higher than that of the possible compounds which would be formed by substituting hydrogen in the OH group with one of the above Bi cations. This phenomenon can be explained, for example, by the reaction of Bi cations with a reactive azido group or by the formation of addition compounds. It is therefore an unknown compound, the structure of which has not yet been elucidated. The percentages of Bi determined by titration and given in the table have been rounded to whole numbers - a certain determination error and the possible presence of impurities must be taken into account. However, in addition to the already mentioned 4,6 dinitroazidophenol, a match was found between the values measured and calculated within a tolerance of ± 1%.

Almost all of the listed starting compounds are, except for 5-nitraminotetrazole and 4,6-DNBF in the form of their sodium salts. Sodium azide is a commercially available compound and others

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»<» 'I * * *. ; i ·. Explosive tetrazoles, prepared by diazotization, the Sandmayer reaction or the reaction of azides with cyanide compounds, are also formed exclusively in the form of their sodium salts. Only 5-nitramonotetrazole and 4,6-DNBF are better excreted in the form of the potassium salt. 5,5-Azotetrazole can also be obtained in the form of other soluble alkali metal salts, e.g. potassium salts, but on the one hand this salt is incomparably more soluble and therefore problems with its isolation from solution would arise and moreover in reactions where perchlorate solutions precipitate. potassium salts should be avoided if possible, as precipitation from more concentrated solutions would result in precipitation of poorly soluble potassium perchlorates. On the other hand, sodium perchlorate, which is formed from sodium salts by double exchange, is about 10 times more soluble at room T and up to 15 times more soluble at boiling. 5,5'-Bis-tetrazolylhydrazine is converted to the soluble sodium salt immediately before the reaction.

The above compounds can be used in the form of all other soluble salts, both metal salts and salts of certain inorganic and organic bases. In all cases, other alkali metals such as lithium, cesium and rubidium can be used. In the case of potassium, cesium and rubidium salts, it is necessary to work in more dilute solutions in order to avoid undesired precipitation of less soluble perchlorates of these metals. Perchlorates of all other metals, on the other hand, are so soluble that their separation from the final compound can be done quantitatively.

Significantly more alkaline earth salts (mainly calcium, magnesium and strontium salts) as well as salts of some other metals such as iron, nickel, cobalt and manganese can be used in the preparation of aromatic polynitrophenol salts. In the case of salts of tetrazole derivatives, it is possible to use all alkali metal salts as well as alkaline earth metal salts, with the exception of the salts of 5,5-azotetrazole, the salts of which with these metals are the least soluble. In the case of the above-mentioned tetrazoles, salts of inorganic and organic bases such as hydrazine, hydroxylamine and guanidine and its amino derivatives can be used.

In all cases, ammonium salts can also be used.

Some of these starting compounds are also hydrates with a stable and variable content of crystal waters. 5,5'-azotetrazolate, 5,5'-bis-tetrazolate are stable pentahydrates, 5,5'-diazoaminotetrazolate is tetra to pentahydrate and 5-nitrotetrazolate is di to tetrahydrate.

The table contains only salts of selected energy compounds. There are, of course, a number of other compounds that can form explosive salts - ie. having one or more substitutable hydrogens - for example salts of 4,6-dinitro-3-hydroxyquinondiazonium, 4,6 dinitro-3-carboxyquinondiazonium, 2,3,6-trinitro-p-azidophenol, 5-azidotetrazole and 5-hydrazotetrazole and others. The advantage of Bi salts is generally their minimal solubility, so that it is · *.

As practical experiments have shown, these salts can be easily precipitated from aqueous solutions, even in the case of compounds such as ⁵ -nitrotetrazole ^, where the main problem is excessive solubility of its salts, including salts of such metals as Pb and Ba. The Bi salt precipitates reliably and is precipitated in almost quantitative yield, which is another significant advantage of the Bi salt. On the other hand, it is necessary to take into account that many salts are so insoluble that they will precipitate in a colloidal - difficult to filter form and that preparation procedures will have to be used to increase the particle size to at least a few microns.

The most interesting property of explosive salts Bi is the ability to initiate injection - ie. energy concentration to the smallest possible point. Even those compounds that are not found to be sensitive to friction or impact by conventional criteria leave a black mark of reaction products at the point of contact of the friction pad on the porcelain plate. Those compounds which show a sensitivity to friction are most sensitive to injection, which directly predestines them for use, for example, in ammunition matches.

In combination with other, generally known components of match compositions, such as non-toxic pyrotechnic oxidizers (potassium nitrate, cesium, Bi oxitrates), non-toxic fuels (AI, Ti, Zr, B), energy components (NC, PETN and other energy materials), and frictionators based on thermally non-conductive materials with a high bt (glasses, Bi sulphides), some of the prepared compounds will be ideal for use in non-toxic match, igniter and general ignition compositions.

Examples of practical implementation

Preparation of precipitation solutions

Preparation of Bi perchlorate solutions:

Pour 24.5 ml of 70% perchloric acid into the solution of Ig oxide Bi and allow to react under gentle heating. Dilute the resulting bismuth perchlorate suspension with water, transfer to a 1000 ml _flask and make up to the mark. The solution has a concentration of about 0.02 g Bi / ml.

Solution No. 2

Pour 220 ml of 70% perchloric acid into 220 g of Bi oxide. Dilute the resulting bismuth perchlorate suspension with water and transfer to a 1000 ml flask. The solution has a concentration of approx. 0.2 g Bi / ml.

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Solution No |

Pour 220 ml of 70% perchloric acid into 220 g of Bi oxide. Dilute the resulting suspension of bismuth perchlorate with water, transfer to a 500 ml flask, thus obtaining a concentration of about 0.4 g Bi / mL.

Preparation of solid oxochlorate Bi:

Dilute decant solution 2 or 3 with an excess of isopropanol. After settling, the precipitated product is filtered off, washed with alcohol and dried.

Preparation of energetic compounds

1) Preparation of basic azide Bi:

Pour about 10% aqueous sodium azide solution into the measured amount of solution No. 1 or No. 2 with vigorous stirring. A white, microcrystalline precipitate begins to form, which, after settling, is filtered off, washed with water and alcohol and dried after suction filtration.

2) Preparation of basic picrate Bi:

Heat about 2% sodium picrate solution and, with vigorous stirring, pour into a measured amount of hot solution CH or CH. During cooling, a crystalline dark yellow product begins to precipitate. After cooling and perfect settling, the product is filtered, washed with water and alcohol and dried after suction.

3) Preparation of basic styphnate Bi:

We use a solution of sodium styphnate - the next procedure is the same as in Example No. 2, with the difference that we precipitate the solutions at boiling and after a red precipitate falls out, boil for a few more minutes. After cooling and sedimentation, the amorphous product is filtered off, washed with water and alcohol and dried after suction filtration.

4) Preparation of basic trinitrofluroglucinate Bi:

We use a solution of sodium trinitroflucinate, the rest of the procedure is the same as in Example No. 2. The product is extremely insoluble and therefore it precipitates in a very fine form, a longer standing is necessary. The product is amorphous, orange in color.

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5) Preparation of basic 5,5'-azotetrazolate Bi (according to the order in the table):

Pour a saturated - about 5% solution of 5,5 - azotetrazolate sodium pentahydrate into a measured amount of solution No. 2 and after complete settling the yellow, amorphous product is filtered, washed with water and alcohol, filtered off with suction and dried.

6) Preparation of basic 5,5-azotetrazolate Bi:

Bring a saturated - about 5% solution of 5,5'-azotetrazolate sodium pentahydrate to a boil and, with vigorous stirring, pour into a measured, boiling solution c.i. The same procedure is the same as in Example 5. In this method, about 5% of the product is lost due to chemical decomposition of the resulting salt in an acidic environment at high T. The resulting product is somewhat more explosive and tends to detonate upon ignition.

7) Preparation of basic 5,5 '- azotetrazolate Bi:

Bring the saturated - about 5% solution of 5,5-azotetrazolate sodium pentahydrate to a boil and pour, while stirring, into about 2% of a boiling solution prepared in advance by dissolving the calculated amount of solid oxochlorate Bi in water. The rest of the procedure is the same as in the previous examples. The compound prepared under these conditions - i.e. in weakly acidic solutions, has the least pronounced explosive properties compared to previous products. However, it maintains sufficient sensitivity to friction.

8) Preparation of basic 5 - nitraminotetrazolate Bi:

Bring the saturated - about 5% solution of potassium 5 - nitraminotetrazolate to a boil and pour into a measured amount of boiling solution no. After cooling and complete settling, the colorless amorphous product is filtered off, washed with hot water and alcohol and, after suction filtration, dried and dried.

9) Preparation of basic 5,5 '- diazoaminotetrazolate Bi:

About 10% of the disodium salt of 5,5'-diazoaminotetrazole tetrahydrate is poured, with constant stirring, into a measured amount of solution No. 2 or No. 3. Using a more concentrated solution, a colorless, rapidly sedimenting precipitate is formed which can be filtered after only a few hours. When using a more dilute solution, a yellowish precipitate is formed which takes at least a day to transition to a well-filterable (non-colloidal) form.

19.

After filtration, washing with water and alcohol, suction filtration and air drying, both products have the appearance of a canary yellow, amorphous product.

10) Preparation of basic 5 - nitrotetrazolate Bi:

About 10% solution of sodium 5 - nitrotetrazolate di - tetrahydrate is added to the quartz and poured with stirring into a measured amount of boiling solution čd or čí2. Precipitation under these conditions occurs slowly, during cooling, and the white, microcrystalline precipitate, after cooling and sedimentation, is filtered, washed with water and alcohol and dried after suction filtration. The reaction can also be performed cold using solution # 3. The next procedure is the same.

11) Preparation of basic 5,5 '- bistetrazolate Bi:

For the reaction we use about 10% solution of 5,5'-bistetrazolate sodium pentahydrate, the procedure is the same as in the previous case and it is also possible to choose boiling or cold preparation. The product is colorless, amorphous.

12) Preparation of basic 5,5 '- bis-tetrazolylhydrazinate Bi:

Prepare an aqueous suspension of 5,5'-bis-tetrazolylhydrazine so that after neutralization with 2 N NaOH about 0.2 - 0.5% sodium salt solution ^of 5,5'-bis-tetrazolylhydrazine is formed. Heat the solution until quench and precipitate dropwise with saturated BiOClO ₄ solution with vigorous stirring. Allow the resulting milk colloidal suspension to boil for a few minutes and, after standing, allow it to stand for several days so that the amorphous product is converted into a more filterable form. We then filter off, wash with water and alcohol and dry. The resulting product is canary yellow.

Note: Optimal results were obtained at pH 3-5. In strongly acidic solutions, unreacted 5,5'-bis-tetrazolylhydrazine reappears partially or completely.

13) Preparation of basic 4,6-dinitrobenzofuroxanate Bi:

A hot saturated solution of potassium salt 4,6 - DNBF was prepared and a melt with a measured amount of hot solution ch. After cooling, crystalline DNBF precipitated by precipitation from the potassium salt in an acidic medium and no reaction occurred. Therefore, a certain amount of organic solvent - acetone - was added, the precipitated DNBF redissolved and the mixture was left for several weeks. Aqueous - acetone solution gradually

20 ’changed color from dark red to dark brown and a brown, microcrystalline precipitate precipitated. After suction filtration and washing with water and then acetone, the product was dried at room temperature.

14) Preparation of basic 4,6-dinitroazidophenolate Bi:

Pour the saturated solution of sodium salt of 4,6-dinitroazidophenol into the measured solution No. 2 with vigorous stirring. A reddish-brown amorphous product begins to precipitate immediately, which gradually turns into a brown precipitate. After standing overnight overnight, the product is filtered off with suction, washed with water and alcohol and dried in an oven.

Industrial applicability

The above compounds excel in high thermal and chemical stability and non-moisture. They are significantly less high explosives than comparable existing explosives, such as dinol or TNRO. At the same time, they provide a sufficiently warm flame and a long thermal impulse and an efficient heat transfer mechanism. sports, hunting and military ammunition.

Compounds with lower sensitivity to mechanical impulses can then serve as additional energy materials in match compositions and in various types of ignition systems of pyrotechnic compositions, electric igniter pills and airbags.

Claims (12)

Patent claims An energy compound with reduced toxicity based on a bismuth salt having the properties of initial explosives, obtained by reacting soluble salts of bismuth with soluble salts of inorganic and organic energy compounds, wherein the soluble salt of bismuth is based on bismuth perchlorate. The energy compound according to claim 1, wherein the cation is a bismuth ion and the anion forms compounds selected from the group of inorganic azides or derivatives of aromatic nitro compounds or nitrogen heterocyclic compounds. The energy compound of claim 2, wherein the bismuth is potentially bound in the form of cations Bi (3+), BiO (+), Bi (OH) ₂ (+), Bi (OH) (2+), (BiO) ₅ OH (4+), Bi ₆ O ₄ (OH) ₄ (6+). The energy compound according to claim 1 and 2, wherein the anion is selected from the group of inorganic azides, polynitrophenols, polynitroazido phenols, polynitrodiazoquinone derivatives, polynitrofuroxanes and five-membered nitrogen heterocycles. The energetic compound according to any one of claims 2 or 3, wherein the type of the particular cation Bi is dependent on the pH of the reaction solution. The energy compound according to claim 1 or 2 or 4, obtained by reacting soluble bismuth salts with inorganic azides. The energy compound according to claim 1 or 2 or 4, obtained by reacting soluble bismuth salts with polynitrophenols such as picric acid (2,4,6-trinitrophenol), styphnic acid (2,4,6-trinitroresorcin), trinitrophloroglucin (2, 4,6-trinitro-1,3,5-trihydroxybenzene), with polynitronitrodiazoquinone derivatives such as 4,6-dinitro-3-hydroxyquinondiazonium and 4,6-dinitro-3-carboxyquinondiazonium, with polythroazidophenols such as 4,6-trinitro-1,3-trihydroxybenzene). dinitro-2-azidophenol and 2,3,6-trinitro-p-azidophenol and polynitrofuroxanes such as 4,6-dinitrobenzofuroxan. . ·. . »4 S * · * •: —... Ί *» ** · *. «* · / \ · * ·· The energy compound according to claim 1 or 2 or 4, obtained by reacting soluble bismuth salts with explosive tetrazole derivatives such as 5,5'-azotetrazole, 5,5'-azooxitetrazole, 5,5'-bis-tetrazole, 5,5 '-diazoaminotetrazole, 5,5'-bis-tetrazolylhydrazine, 5.nitramino-1H-tetrazole, 5-nitro-1-H-tetrazole, 5-azido-1H-tetrazole and 5-hydrazo-1H-tetrazole. A process for the preparation of energy compounds with reduced toxicity based on a bismuth salt according to any one of the preceding claims by reacting soluble salts of bismuth with soluble salts of inorganic and organic energy compounds based on azides, aromatic nitro compounds or nitrogen heterocyclic compounds. A process for preparing a soluble bismuth salt for the production of an energetic compound as defined in any one of claims 1 to 8, wherein the soluble bismuth salt is formed by reacting concentrated perchloric acid with metallic bismuth, its oxides or oxocarbonates to form bismuth perchlorate which hydrolysis to soluble bismuth oxochlorate. Use of a soluble bismuth salt in the form of bismuth oxochlorate, prepared according to claim 10, as a precipitant for the production of an energetic compound as defined in any one of claims 1 to 8. Use of bismuth salts with reduced toxicity, as defined in any one of claims 1 to 8, as main or auxiliary energy compounds in matches for ammunition and cartridges with central and peripheral ignition for sports, hunting and military ammunition, or as additional energy compounds for matches and into various types of petrol pyrotechnic compositions, electric torch pills and airbags.